Re: [MIPS] Import updates from i386's i8259.c

Re: [MIPS] Import updates from i386's i8259.c

[Christoph Hellwig]

On Wed, Dec 06, 2006 at 08:15:47PM +0000, linux-mips@linux-mips.org wrote:
> Author: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Thu Dec 7 02:04:17 2006 +0900
> Comitter: Ralf Baechle <ralf@linux-mips.org> Wed Dec 6 20:10:54 2006 +0000
> Commit: bf8cfe1360932f191a3ea8d47c773c008ec32cd7
> Gitweb: http://www.linux-mips.org/g/linux/bf8cfe13
> Branch: master
> 
> Import many updates from i386's i8259.c, especially genirq transitions.

Shouldn't we try to share i8259.c over the various architectures that
use this controller?  With the generic hardirq framework that should be
possible.

Re: [MIPS] Import updates from i386's i8259.c

[Alexander Voropay]

"Christoph Hellwig" <hch@lst.de> wrote:

>> Import many updates from i386's i8259.c, especially genirq transitions.
> 
> Shouldn't we try to share i8259.c over the various architectures that
> use this controller?  With the generic hardirq framework that should be
> possible.

 The "i8259" should be under "ISA" or "EISA" Kconfig option.
AFAIK, all known ISA chipsets contains dual i8259 controllers:
LPC on the PCI-ISA bridge (Cobalt, Malta, ...), 
Intel 82430 EISA Mongoose chipset (Indigo2 IP22, Magnum/Jazz, SNI RM-200, ...)

--
-=AV=-

Re: [MIPS] Import updates from i386's i8259.c

[Alexander Voropay]

"Christoph Hellwig" <hch@lst.de> wrote:

>> Import many updates from i386's i8259.c, especially genirq transitions.
> 
> Shouldn't we try to share i8259.c over the various architectures that
> use this controller?  With the generic hardirq framework that should be
> possible.

 The "i8259" should be under "ISA" or "EISA" Kconfig option.
AFAIK, all known ISA chipsets contains dual i8259 controllers:
LPC on the PCI-ISA bridge (Cobalt, Malta, ...), 
Intel 82430 EISA Mongoose chipset (Indigo2 IP22, Magnum/Jazz, SNI RM-200, ...)

--
-=AV=-

Re: [MIPS] Import updates from i386's i8259.c

[Sergei Shtylyov]

Hello.

Alexander Voropay wrote:

>>> Import many updates from i386's i8259.c, especially genirq transitions.

>> Shouldn't we try to share i8259.c over the various architectures that
>> use this controller?  With the generic hardirq framework that should be
>> possible.

> The "i8259" should be under "ISA" or "EISA" Kconfig option.

    It's not really bus specific actually. I'm sure MCA systems had it as well.

> -- 
> -=AV=-

WBR, Sergei

Re: [MIPS] Import updates from i386's i8259.c

[Ralf Baechle]

On Thu, Dec 07, 2006 at 10:46:39AM +0100, Christoph Hellwig wrote:

> On Wed, Dec 06, 2006 at 08:15:47PM +0000, linux-mips@linux-mips.org wrote:
> > Author: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Thu Dec 7 02:04:17 2006 +0900
> > Comitter: Ralf Baechle <ralf@linux-mips.org> Wed Dec 6 20:10:54 2006 +0000
> > Commit: bf8cfe1360932f191a3ea8d47c773c008ec32cd7
> > Gitweb: http://www.linux-mips.org/g/linux/bf8cfe13
> > Branch: master
> > 
> > Import many updates from i386's i8259.c, especially genirq transitions.
> 
> Shouldn't we try to share i8259.c over the various architectures that
> use this controller?  With the generic hardirq framework that should be
> possible.

See http://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=20061206203259.GA10170%40linux-mips.org ;-)

The MIPS version of i8259 is already sharable that is all the code that
doesn't immediately deal with the i8259 PIC has been removed.  A few
small things will need still need attention.  i386 uses this silly
optimization in cached_master_mask / cached_slave_mask that depends on
little endian byte order.  i386 programs ICW2 with 0x20 while MIPS uses
I8259A_IRQ_BASE.  And the i386 version has various stuff such as the FPU
interrupt handler which are not immediately i8259A-related in i8259.c.

  Ralf